1. Field of the Invention
The present invention is broadly concerned with improved, bendable installation fins adapted for securement to window or door assemblies to facilitate site installation thereof in a building wall. More particularly, the invention pertains to a preferably aluminum installation fin having a fold line therein formed by a plurality of elongated, aligned, obliquely oriented depressions formed in one face of the fin body, as well as a method of forming such fold line structure through the use of a knurling wheel. Installation fins in accordance with the invention are lower in cost, retain their integrity through multiple bend cycles, and completely eliminate the apertures of prior fins, which require separate application of sealing tape and can lead to water leakage around the window or door frame during use.
2. Description of the Prior Art
Most commercial fenestration products (e.g., doors and windows) are provided with factory-installed circumscribing frames. These frames are normally equipped with elongated installation fins which are initially attached in a recessed or flattened condition adjacent the outer frame surfaces. In use, the fins are manually pivoted outwardly through essentially a 90.degree. arc so as to form outwardly extending projections about the door or window frame. During installation, the window or door assembly is mounted in an appropriate rough opening in the building wall, and nails or screws are installed through the fins to attach the door or window assembly in place.
A common fin design uses a dual durometer plastic material where a soft material is used to allow folding of the fin. Such synthetic resin fins have the drawback of becoming brittle in cold weather and being perceived as being lesser quality than metal fins. Another fin design is described in U.S. Pat. No. 5,210,986 wherein aluminum fins are provided. These fins are designed with a fold line to make the fin manually bendable on-site. In particular, the '986 fins have a series of small holes punched in the fin bodies to define the necessary fold line. The holes are in turn covered with a tape which is designed to prevent water leakage through the holes when the fenestration product is installed in a building. Although fins produced in accordance with this patent are a significant advance in the art, one drawback is that the sealing tape is expensive and therefore the fins are not as economical to manufacture as one-piece metal fins. Furthermore, the sealing tape can become punctured or dislodged during the installation process, thereby presenting a potential leakage problem.
There is therefore a need in the art for an improved installation fin which is of essentially one-piece, integral design and which avoids the costs and problems associated with fold line structure in the form of tape-covered apertures through the fin body.